Apparatus for trimming or pinking leather or the like



Feb. 15, 1938. s. E. ROSENBERG 2,108,178

APPARATUS FOR TRIMMING OR PINKING LEATHER OR THE LIKE Filed Feb. 24,.1936' 2 Sheets-Shee't 1 m", m ']izwW Fb. 15, 1938. s. E. ROSENBERGAPPARATUS FOR TRIMMING OR PINKING LEATHER OR THE LIKE 2 Sheets- 311691 2Filed Feb. 24, l956 Patented Feb. 15, 1938 UNITED STATES APPARATUS FORTRIMIVHNG OR PINKING LEATHER OR THE LIKE Stig E. Rosenberg, Brockton,Mass.

Application February 24, 1936, Serial No. 65,200

4 Claims.

This invention relates to a method of and apparatus for trimmingmarginal portions of a piece of leather or the like, the trimming orpinking cuts being such as to leave a beveled edge.

It is an object of the invention to provide apparatus for cutting anon-straight marginal portion of a piece of leather, such as a part fora shoe upper, so that the entire portion to be trimmed is operated uponwith one stroke only. It is another object of the invention to provideapparatus by which a non-straight marginal portion of a piece of leathermay be pinked on a bevel in such a manner that each of the scallopsalong the edge projects in a direction perpendicular to the direction ofthe edge at that point.

Various other advantageous features of the in.- vention will be apparentto one skilled in the art from a disclosure thereof in the descriptionof certain embodiments which follows, and on the drawings of whichFigure 1 is a plan view of apparatus embodying the invention, designedfor pinking a shoe vamp.

Figure 2 is a side elevation of the same, a portion being broken away toshow in section.

Figure 3 is a section on the line 33 of Figure 1, this view being. on alarger scale.

Figure 4 is a fragmentary portion of Figure 3 showing the parts in adifferent position of operation.

Figure 5 is similar to Figure 4, showing a further step in the operationof the apparatus.

Figure 6 is similar to Figure 4 except that a backing sheet is shown inaddition.

Figure 7 is a fragmentary perspective view of a marginal portion of apiece of leather or similar sheet material after being operated uponaccording to the invention.

Figure 8 is a fragmentary sectional view of apparatus for bevel-trimmingleather or the like.

Figure 9 is a perspective view of a shoe vamp having edge portionsthereof bevel-trimmed.

Figure 10 is a fragmentary View of apparatus for bevel-trimming a pieceof leather.

Figure 11 is a fragmentary perspective view of a piece-of leather havingan edge portion trimmed on a bevel.

Referring to the drawings in detail, a die suitable for carrying out theinvention is illustrated in Figures 1 and 2. As illustrated, this diemay consist of a base block on which is mounted a stationary supportingplate or table 22, the supporting plate having a beveled edge (Cl. Ml-23 portion 23 which is shaped to conform to the contour of the portionof the work which is to be trimmed or pinked. By way of example, a shoevamp 25 is shown as the work which is to be pinked. As illustrated inFigure 1, the vamp 25 is of the well known wing-tip shape, the upper orinner edge of which is to be pinked prior to being sewed to otherportions of the upper. Mounted at suitable points on the base block 20are gage pins 28. The pinking cutter is in the form of a knife having asharp cutting edge following the configuration of the bevel edge 23 ofthe supporting plate 22, the knife as shown being integral with ahorizontal back 3| which rigidly maintains the blade 30 in its shape.

As indicated in Figures 2 and 3, the pinking knife 30 has a blade ofuniform width (or height) and of substantial thickness sufficient forthe formation of a zigzag cutting edge by V notches or grooves in theside faces of the blade, the surface defined by the cutting edge havinga substantially uniform bevel and being complemental to the surface 23of the work-supporting table 22.

As indicated in Figures 3 to 6, the knife 30 has a beveled cutting edge32 conforming to the bevel of the plate edge 23, so that, when the knifedescends in a cutting operation, the entire cutting edge simultaneouslyengages the bevel edge 23 of the supporting plate. As shown, the knifemay be secured to the under face of a suitable plate 34 which in turn ismounted on a plurality of pillars 36, the pillars extending intosuitable cavities 38 in the block 28 and being pressed upwardly bysprings 41? in the cavities 38, as indicated in Figure 2. The plate 34and the knife back 3! are provided with suitable apertures 42 and 43respectively, above the gage pins 28 so as to permit the operator to seethe pins and the marginal portions of the work immediately in contacttherewith before the knife descends. The operation of the pinkingmechanism is indicated in Figures 4 and 5. In using the apparatus, theoperator places a vamp or other piece of work on the supporting plate 22and pushes it until it engages the several gage pins 28, sighting thegage pins through the apertures 42 and 43 to see that all are engaged bythe work. Since the bevel edge 23 conforms to the marginal portion ofthe vamp to be pinked, this marginal portion overhangs the bevel edge 23as indicated at 46 in Figure 3. The plate 34 with the knife 3!! is thencaused to descend by any suitable means so that the knife 30 engages theoverhanging portion 4.6 of the work. This overhanging portion is thuspushed down out of the plane of the work, as indicated in Figure 4, sothat all portions of the marginal part to be pinked are at an angle tothe plane of the work. Further descent of the knife 30 causes thecutting edge to penetrate through the bent marginal portion 46, asindicated in Figure 5. It is evident from this figure that the knife 30cuts the leather at an acute angle to the surface thereof, thus making abevel cut. In pinking a marginal portion of a vamp or other part of ashoe upper, it is desirable that each of the scallops or serrationsalong the edge project in a direction perpendicular to the edge of theleather at that point, that is, in the direction of the radius ofcurvature of the edge at such point. To this end the pinking knife 36may be constructed as indicated in Figure 1 so that the scallops,serrations, or other individual projections along the edge will extendin the proper directions, as indicated in Figure '7, wherein are shown aseries of serrations 58 arranged along a curved edge, each of theserrations extending in the direction of the radius of curvature of theedge at that point. r

The supporting plate 22 is preferably of some relatively soft metal suchas brass or aluminum, so that, if the knife 30 cuts into the face of thebevel edge 23 slightly, the cutting edge of the knife will not beinjured. In some cases, it may be desirable to provide a backing layerto overlie the supporting plate 22 and to receive the cutting edge ofthe knife after it has penetrated through the marginal portion 46 of theleather or other piece of material to be trimmed or pinked. Such abacking layer is indicated at 50 in Figure 6. It may be made of anysuitable material such as a fibrous sheet having sufficient elasticityto give properly without cracking or buckling along the marginal portionwhen the margin is bent down as indicated at 52.

Figure 9 illustrates a shoe vamp having an edge portion 56 cut on abevel. As shown, this shoe vamp may also have decorative perforations 58with beveled edges, the perforations having preferably been previouslypunched as at 68 before the edges thereof are trimmed. The beveled edgesmay be cut by means of a die similar to that illustrated in Figures 1and 2 except that the knife 62 has a shape suitable for the desiredbevel out instead of being provided with scallops or a zig-zag edge asshown in Figure 1.

Figure 10 illustrates a support plate 10 having a relatively steepbeveled edge 12. A knife 14 is mounted in the manner indicated inFigures 1 and 2 so as to push the marginal portion 46 of a piece ofleather out of the plane of the piece and against the bevel surface 12.The knife then descends to make a bevel cut on the marginal portion ofthe leather at a relatively small angle with the face of the leather,such a out being somewhat similar to a skiving cut, as indicated at 16in Figure 11.

It is evident that various modifications and changes may be made in theinvention as herein shown and described without departing from thespirit or scope thereof as defined in the following claims.

1. A pinking die comprising a horizontal supporting table for a piece ofleather, said table having a beveled edge portion similar in contour tothe edge portion of the leather to be trimmed, gage pins engageable bysaid edge portion of the leather, means supporting said gage pinsadjacent to said beveled edge portion of said table, a knife-supportingplate yieldingly mounted over said table, a knife mounted on the underside of said plate, and means guiding said plate so that downwardmovement thereof brings said knife into contact with said beveled edgeof the table, said plate having apertures therethrough above said gagepins to permit sighting of said pins and the portions of the workadjacent thereto.

2. A die for bevel-trimming or pinking leather or the like, comprising abase, a wor supporti ng table secured on said base, said table having abeveled edge portion, a knife-supporting plate mounted above andresiliently supported by said base, and a knife secured to andprojecting down from said supporting plate, the cutting edge of theknife having a shape corresponding to the shape of said beveled edgeportion of said table.

3. A die for bevel-trimming or pinking leather or the like, comprising abase, a work-supporting table secured on said base, said table having abeveled edge portion, a plurality of gage pins mounted on said baseadjacent to said beveled edge portion, a knife-supporting plate mountedabove and resiliently supported by said base, said plate being providedwith sighting apertures above said gage pins, and a knife secured to andprojecting down from said supporting plate, the cutting edge of saidknife having a shape corresponding to the shape of said beveled edgeportion of said table.

4. A pinking knife for bevel-pinking shoe upper parts, said knifecomprising a blade of uniform width and substantial thickness shaped tocorrespond to the edge of the work to be pinked, the upper and loweredges of said blade being disposed respectively in parallel horizontalplanes when the knife is in use, said lower edge being formed with azigzag cutting edge defining a bevel surface at a constant angle to thevertical throughout the length of the knife.

STIG E. ROSENBERG.

